1990 Class A Transmission Oil Leak

[nhcouple]

Hi!

1990 Class A Ford Motorhome with auto trans. Started our trip south, on a long hill noticed smoke, it appeared trans fluid running down the side of the trans somewhere above the shift linkage. Trans shifts fine, possible over full by half quart. Only happens on very steep grades not at idle or regular travel.

Thanks in advance!

Kevin

[auto]

If it was over full it may be blowing out the vent on top when it gets hot on hills.